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Discussion Starter #1
I was watching this Valentino Rossi race tutorial and I was following along with no problems until he said, "You have to get the front tire to turn at a slower speed than the rear tire" (or the other way around - I forget).

Now unless one locks up one of the brakes, is doing a burnout or some other similar maneuver/stunt, how in the heck can you have one wheel spinning slower or faster than the other while riding.......much less at 100mph+?

I've been riding for over 25 years and thought I knew how to ride. I guess it's time for a refresher!!

http://www.ebike-ridingtips.co.uk/video/mediaplayer.swf?file=rossi.flv
 

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Though I'm not very smart about such things, I'll take a stab:

Would it be from the front wheel taking a narrower arc than the rear wheel around a corner?
 

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It's a bit like when you rode a bike as a kid. In pre BMX days the tires were a little slicker so it was easier. To impress a pre-teen girl when you were a pre-teen boy you would ride up to her and her friends on your Mustang or Raleigh Chopper, lock the rear wheel, lose traction and with a little body weight shifting you could stop sideways with a flourish.
What happens in racing is that when you are entering a tight corner you slow up the back wheel a bit which loses some ( but not all !!!) traction, do the body weight bit which makes the back of the bike slide around and point in the direction that you want to go. When you are pointed in the right direction you let the 200 horses loose and head off where you want to go.
Nicky Hayden is very good at it being an old dirt tracker when he was young.
Make sense?
 

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I remember watching the pre race for a Daytona 200 race, where they had telemetry on one of the bikes on the track. The back wheel was turning about 15 mph faster than the bike was actually travelling, indicating quite a bit of slip from the rear tire.

Not really relevant to the question, but interesting nonetheless.
 

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When you enter a turn hard under braking, you can trail brake to get the rear to kick out and apply hard throttle which spins up the rear about 20 -30 mph faster than your forward movement. What it does is allow you to brake later, square off the turn and get on the throttle quicker. Faster rear wheel speed then front!:D

http://www.youtube.com/watch?v=asou3VN_iQI&eurl=http://www.triumphrat.net/riding-and-survival-skills/98560-skill-question-downshifting.html&feature=player_embedded

Cheers

Jeff:motorbike2:
 

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Discussion Starter #9
It's a bit like when you rode a bike as a kid. In pre BMX days the tires were a little slicker so it was easier. To impress a pre-teen girl when you were a pre-teen boy you would ride up to her and her friends on your Mustang or Raleigh Chopper, lock the rear wheel, lose traction and with a little body weight shifting you could stop sideways with a flourish.
What happens in racing is that when you are entering a tight corner you slow up the back wheel a bit which loses some ( but not all !!!) traction, do the body weight bit which makes the back of the bike slide around and point in the direction that you want to go. When you are pointed in the right direction you let the 200 horses loose and head off where you want to go.
Nicky Hayden is very good at it being an old dirt tracker when he was young.
Make sense?
I understand what you are saying and maybe I misunderstood the video, or this portion, from the beginning. I didn't think he was talking about "drifting" his bike. I thought he was merely talking about different ways (offensive, defensive, and racing) of hitting the curves.

I will go back and watch it again....
 

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I understand what you are saying and maybe I misunderstood the video, or this portion, from the beginning. I didn't think he was talking about "drifting" his bike. I thought he was merely talking about different ways (offensive, defensive, and racing) of hitting the curves.

I will go back and watch it again....
Forgot to mention that this is whilst you are still peddaling and applying the front brake.......

It's a way of getting the bike slowed up asap, getting into the corner and pointed in the right direction so that you can get out of the corner in a hurry. All this while Mr Stoner is rubbing elbows with you.
 

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Regarding powersteering, I have done this. the way i achieved it is coming into sharp corner with a lot of braking I blipped the throttle and shifted down a couple of times with enough throttle on that the rear wheel is slipping out. Then as soon as I see the exit I go WOT and the rear slides out nicely and then straightens up. After doing this repeatedly for several corners you find out that you can slip the bike very easily under the combined brake and downshift engine braking. Using both together is also easy, if coming out of the corer you stay aggressive and don't get off the throttle too suddenly, the physics will work to get you out of the corner upright and going like hell. getting off the throttle suddenly probably would not be good.

It helps to be younger than 25 years old and never hesitate.
 

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..............What happens in racing is that when you are entering a tight corner you slow up the back wheel a bit which loses some ( but not all !!!) traction, do the body weight bit which makes the back of the bike slide around and point in the direction that you want to go. When you are pointed in the right direction you let the 200 horses loose and head off where you want to go.
Nicky Hayden is very good at it being an old dirt tracker when he was young.
Make sense?
Yep, it's how motor-x's go into and out of a berm !


How it's done in moto-x. You can apply it similarly in track racing but without the berm or without locking the back wheel, just slow it down.

Berms.

.............The best line is usually to enter the berm high and then turn and drive down the face as you exit. Stay smooth through the berm, squaring off by locking the back wheel to slide it around and then driving down the face.



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Ride on !
 

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i don't know because i'm not Freddy Spencer, but my experience was that it worked via combination of engine braking and actual brake action. but when i did it I only had a rear drum. To get enough enough engine braking I had to downshift, which helped me because I transitioned to a mild power slide coming out.And you really need to be "putting it to her" to do this on an ordinary street bike.I never watched a tape of myself doing it but theres a lot more disruption, if thats the right word with a street bike, going hard on decell and acell. Yeah, its basically a form of the little boys "skid turn" going onto the turn and then throttle to maintain the slide and gradualy tapering off to straight accell coming out of the turn.

Unless you are running for your life in an extreme emergency (like for instance from zombies) this is not advisable, especially not advisable on a HD.
 
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